LENAERS Guy

Project status: active

At the Angers University Hospital’s Health Biology Institute, Guy Lenaers and Sophie Boucher are conducting research into the genetic causes of age-related hearing loss, also known as presbycusis. The aim is to investigate the role of genes contained in the mitochondria, the “factories” where cells produce energy. This original approach could lead to innovative prevention strategy and treatments.

Presbycusis is natural hearing loss that occurs with age and the leading cause of deafness in adults. However, we are not all equal in the face of this aging process, which results from an interplay of genetic and environmental factors (noise exposure, toxins, tobacco, etc.) and associated diseases (diabetes, high blood pressure, etc.). “Environmental factors and certain pathologies cause stress that alters the genetic material (DNA) of mitochondria*. Remember that these structures, which are very numerous inside the cell, supply the energy it needs,” explains Guy Lenaers, director of the MitoLab team at the Health Biology Institute in Angers. “Over time, mutations accumulate and the mitochondria become less efficient. Yet hearing, which functions continuously, requires a lot of energy. Our hypothesis is that hearing function deteriorates with age due to the accumulation of mutations in mitochondrial DNA.”“Fondation Pour l’Audition’s recognition of the relevance of our study is very important. It underlines the significance of the innovative concept we are developing, the link between mitochondria and age-related hearing loss. This support will allow us to accomplish this project, in particular with the hiring of a qualified person to analyze the large amount of molecular data that will be generated.”From clinics to genetics

Conducted jointly with Dr. Sophie Boucher, an ENT surgeon at Angers University Hospital, the project aims to validate this hypothesis. Responsible for the clinical part, Dr. Boucher summarizes the approach: “We’re going to study all the mitochondrial genetic material from 100 patients aged 40 to 80 with severe presbycusis and compare it with material from a similar group of 100 people with normal hearing. For each participant, the identified genetic mutations will be analyzed in light of their pathologies and exposure to environmental factors over their lifetimes. We should be able to identify whether mitochondrial genetic defects lead to presbycusis and which risk factors are involved.”

If the study confirms that mutations in mitochondrial DNA contribute to age-related hearing loss, it will pave the way for preventive strategy, improved diagnosis and therapies to maintain hearing health as we age.

Professor Guy Lenaers
Researcher
Director of MitoLab Laboratory, MitoVasc, Angers University Hospital, France

* Mitochondria: small structures present inside each cell, responsible for producing the energy required for all biological reactions. They have their own genetic make-up, inherited only from the mother.